Flat board type brushless dc motor

ABSTRACT

A flat board type brushless DC motor is invented comprising a stator core having a laminated flat core structure of a ring type which is slotted a constant distance slot for installing the teeth core and winding the exciting coil on the inner or outer circumference of a stator core circle. The teeth core has a constant thickness with a certain number of teeth. The rotor faced against the stator is consisted of the rotor shaft, the circular flat rotor frame fixed on the motor shaft and assembled with even number of the N- and S-permanent magnets on the circle flat rotor of the flat type brushless and synchronous motor.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a flat board type brushless DC (BLDC)motor which has more than one plate stator and rotor structure. Moreparticularly, the stator structure consists of the slotted laminationstator core and laminated stator teeth core. The rotor structureconsists of a magnetic plate core installed with a permanent magnet or alaminated rotor core with a die-casting aluminum or copper of the shortcircuit configuration. The stator and rotor are faced each other. TheBLDC motor is basically configured a housing frame with stator, shaft,rotating frame with rotor and bearings. The multi flat board type BLDCmotor forms more than one structure of the stators and rotors. The flatboard type BLDC motor of the present invention is able to increase theoutput power by using wider diameter against axial length per unitvolume. So, it is possible to vary the capacity of output power byadopting the multiple stators and rotors to produce the higher power.

2. Related Prior Art

A conventional motor is made of the stator and rotor of a cylindricaltype. FIG. 1 shows the conventional stator configure with the slottedcore, which is axially laminated, for the winding coil. Also theconventional rotor has the configuration of a cylindrical type in theinner of the stator core like FIG. 2.

As shown FIG. 2 a, the permanent magnet rotor is installed as an arraypermanent laminated, for the winding coil. Also the conventional rotorhas the configure of a cylindrical type in the inner of the stator corelike FIG. 2.

As shown FIG. 2(a), the permanent magnet rotor is installed as an arraypermanent magnet for making the magnetic pole on the rotor surface. FIG.2 b shows the rotor of the conventional induction motor which is made ofthe aluminum die-casting or copper. The conventional motor, which isconsisted of the above stator (FIG. 2 a) and rotor (FIG 2 b), is theFIGS. 3 a and 3 b. The effective section area(S_(eff) of a conventional motor is calculated as the product, S)_(eff)=μD_(eff)L_(eff), of the inner diameter (D_(eff)) and thelaminated core axial length (L_(eff)) of stator.

To increase the power capacity of motor, the laminated axial core length(L_(eff)) of stator and rotor must be changed and extended. Otherwisethe diameter (D_(eff)) of motor must be extended. These case methods arecause of the weight and volume of motor and it will be higher theproduct cost of motor according to the material cost.

SUMMARY OF THE INVENTION

The object of invention is to provide the flat type motor with morelarger the diameter than the axial length of motor to product the hightorque density per unit volume and the flat type motor with thestructure of flat type to easily fit and increase the number of thestator and rotor due to the demand of the output power capacity. Becauseof the invention case of the motor with the multi stator and rotor, weare called as the multi flat type motor. This flat type motor isconsisted of the flat stator, the flat rotor, the shaft and the housingframe.

The structure configuration of the stator (FIG. 6) is consisted of thelaminated magnetic teeth core (FIG. 4 b ) with the multiple teeth corefor winding coil, the laminated magnet stator (FIG. 4 a ) with themultiple slots for the install of the laminated teeth core and the backiron plate frame as shown FIG. 5.

The flat type rotor is installed on the shaft for the rotating againstof the flat type stator.

the structure configuration of the flat rotor is consisted of thepermanent magnet and the back iron flat for a permanent magnet motorsuch as a brushless DC motor and a synchronous permanent magnet motor.On the other one, for a flat type induction motor, the structureconfiguration of the flat rotor has the same structure such as the flatstator of FIG. 5. But the flat rotor has the aluminum die-casting or thecopper short circuit as shown FIG. 9 a and FIG. 9 b in the stead of thewinding coil of stator.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is the drawing of the conventional cylindrical stator core.

FIG. 2 a and FIG. 2 b are the drawings of the conventional cylindricalrotor core.

FIG. 3 a and FIG. 3 b are the drawings of the conventional cylindricalmotor structure made of the magnetic stator core and rotor core of FIG.1 and FIG. 2.

FIG. 4 a is this invention drawing which is described the magneticstator core having the inner and the outer slotted core configurationfor the inserting and the fitting of the laminated teeth core.

FIG. 4 b is this invention drawing which is described the teeth core ofa flat type motor.

FIG. 5 is this invention drawing which is described the stator core of aflat type motor.

FIG. 6 is this invention drawing which is described the stator assembledthe stator and the teeth core together.

FIG. 7 a is this invention drawing shown at the front view for thepermanent magnet rotor of a flat type motor and FIG. 7 b is thisinvention drawing of the rotor assembled the permanent magnet and theback iron flat.

FIG. 8 a, 8 b and 8 c are these invention drawings of the single module,the dual module and multi module flat type motor for the permanentmagnet brushless and synchronous motor.

FIG. 9 a is this invention drawing which is described the rotor of aflat type motor against the rotor of the conventional induction motor.

FIG. 9 b is this invention drawing of the rotor structure assembled onthe rotating shaft for a flat type motor against a induction motor.

FIG. 9 c is this invention drawing of a flat type induction motorassembled a flat stator and a flat rotor on the shaft together.

FIG. 10 a is this invention drawing of the dual flat type inductionmotor with the two stator and two motor.

FIG. 10 b is the invention drawing of the multi flat type inductionmotor.

BEST MODE FOR CARRYING OUT THE INVENTION

Due to the drawing, this invention can be carried out as followings. Theflat type motor of this invention has the structure assembled the flatstator (1), the flat rotor (2) and the housing (6) shown FIG. 4 throughFIG. 8. The above housing (6) is made to support the shaft axis of rotorwhich is installed to rotate the rotor (2) against the stator (1)assembled the multi laminated stator core (FIG. 4 a) and the teeth core(FIG. 4 b). The above stator (1) is installed in the side of the housing(6) and made of the laminated stator core (3) and the laminated teethcore (4).

The stator core (3) has the laminated flat core structure of a ring typewhich is slotted a constant distance slot for the install of the teethcore (4) and the winding of the exciting coil (10) on the circumferenceof a stator core circle.

The stator slot (3 b) of the above stator core (3) has the structureconfigure which is made of the multi slot with a constant distance onthe inner or outer circumference of a stat core circle in order toinstall the teeth core (4).

The above teeth core (4) has a constant thickness which is consisted ofa number of teeth core. Similarly, the above stator core (3) has aconstant thickness which is consist of a number of stator core.

The rotor (2) against the above stator (1) is consisted of the rotorshaft (8) and the circle flat rotor frame (5) fixed on the motor shaftand is assembled the permanent magnet (7) of the N and S-pole on thecircle flat rotor for the regular magnetic pole. The above rotor shaft(8) is connected to the bearing fixed at the motor housing frame (6).The permanent magnet (7) has the even magnetic pole array of N and Spole according to the magnetic pole number of motor.

As shown FIG. 8 a, 8 b and 8 c, in order to increase the torque ofmotor, the number of stator frame (5) which is consisted of the statorcore (3) and the teeth core (4) and the number of the rotor frame (5)which is made of the permanent magnet for a permanent magnet brushlessmotor and synchronous motor or the short circuit flat type (FIG. 9 a)for the flat type induction motor must be added.

As shown FIG. 9 a and FIG. 9 b, the rotor of this invention is consistedof the rotor core and teeth core such as the stator core(3) and theteeth core (4) for the flat type induction motor against theconventional induction motor. To flow the induced current on the flattype rotor, the rotor (14) has the short circuit conductor (11) with thealuminum die-casting conductor or the copper.

As above the expressions, the flat type motor of this invention has thestructure which the diameter of motor is larger than the axial length ofmotor. And the flat type motor has the laminated magnetic stator core asthe drawing of 4 a and 4 b and the laminated teeth core as the drawingof 5 for the magnetic circuit path from the exciting winding current andthe flat type permanent magnet rotor.

Also, The winding of the above teeth core, as shown the drawing of 5, islocated and fixed at the span of the teeth core and the teeth core. Thestator core (3) coupled with the teeth core (4) is fixed at the housingframe as shown the drawing of 6.

In this invention, the effective area (A_(eff)) for the production ofmotor torque is calculated by the difference of the area of outerdiameter (π D² _(OUT)/4) and the area of inner diameter (π D² _(in)/4)about the circle flat stator. If the diameter of motor is a constant,the capacity increment of the flat type motor can be used and satisfiedas the addition of a unit flat type motor as shown the drawing of 8 a onthe same rotating shaft. It is possible to design and manufacture theflat type motor on the same rotating axis for the double and the multiflat type motor which is made of the unit flat type motor. So that, itis easy to manufacture the flat type motor and it is possible to makethe structure which the flat type motor can be produced the high torqueper unit volume. The shape of the permanent magnet and the teeth core isdesigned to minimize the cogging torque and the torque ripple.

The specification according to the voltage and the pole number of theflat type motor is designed and manufactured on the base of the unitflat type motor. The number of slot (Z₁) for the flat type motor isdecided from the below equation as functions of the phase number (m),pole number(P) and the slot number per phase per pole(q).Z₁=mPq   (math. equation)

Also, the winding coil (10) of the flat type motor is decided by thepole number and the winding method and the teeth number of the rotor isselected to minimize the vibration and the noise as the combination ofthe teeth number of the stator and the magnetic pole number of therotor.

This invention is proposed that the motor has the structure with morethe larger diameter than the axial length of the motoe when theconventional motor is compared. So that, it can be easily manufacturethe thin flat type motoe of the short length axis and the largediameter. Also, to increase the demand power capacity, if the unit flatstator and rotor is added and assembled on the shaft, it is possible tomake the unit flat type, the double flat type and the multi flat typemotor with more the high efficiency and the torque per unit volume thanthe conventional motor.

The torque of the flat type motor depends on the difference area of theouter diameter section area and the inner diameter section area but thetorque of a conventional motor depends on the product,S_(eff)=μD_(eff)L_(eff), of the inner diameter(D_(eff)) and thelaminated core axial length(L_(eff) of stator. So that, the flat type motor can produce the high torque with more the small volume and the light weight per the input power than the conventional motor and make the thin axial motor with more the larger diameter than the axial direction thickness.)

This invention is described about the executive example as the drawingand the explanation. And this inventior would like to clear up that thisinvention can be exchanged and reformed within the invention objectiveand mind by the other reader who has the general know-how andinformation.

1. A flat board type brushless DC motor, comprising: a housing whichsupports a rotor through an assembly with a plurality of stators and isinstalled against said stators; a stator which consists of a stator corehaving a ring type laminated flat structure and a plurality of teethcores each having winding coil and are slotted at a constant distance oninner or outer circumference of a stator circle; and a rotor which has aplurality of magnets that are installed in order to fix a circle flatrotor frame on a rotor shaft which is fixed through a bearing in saidhousing and to face against the teeth core on one face of rotor framewhich faces said teeth core.
 2. The motor as claimed in claim 1, whereinsaid stator further includes a laminated flat core structure of a teethcore (4) and a stator core; and said stator core has a structureconfiguration which is made of the multi slots with a constant distanceon the inner or outer circumference of a stator core circle in order tobe installed and said teeth core has a constant thickness which isconsisted of a number of teeth core.
 3. The motor as claimed in claim 1,wherein magnets which are installed on said rotor faces each of teethcore where said coil is wound and has even number of magnetic pole arrayof N and S pole according to the magnetic pole number of motor.
 4. Themotor as claimed in claim 1, wherein a plurality of said magnets areinstalled along the axial direction of the rotor to increase the rotatorframe and a plurality of stators are installed in the housing in orderto face against said magnets in order to increase the torque of themotor.
 5. A flat board type brushless DC motor, comprising: a housingwhich supports a rotor through an assembly with a plurality of statorsand is installed against said stators; a stator which consists of astator core having a ring type laminated flat structure and a pluralityof teeth cores each having winding coil and are slotted at a constantdistance on inner or outer circumference of a stator circle; and a rotorwhich has a induction motor that are installed in order to fix a circleflat rotor frame on a rotor shaft which is fixed through a bearing insaid housing and to face against the teeth core on one face of rotorframe and is consisted of a plurality of teeth cores which are insulatedby short circuit rings which faces said teeth core.
 6. The motor asclaimed in claim 5, wherein said stator further includes a laminatedflat core structure of a teeth core (4) and a stator core; and saidstator core has a structure configuration which is made of the multislots with a constant distance on the inner or outer circumference of astator core circle in order to be installed and said teeth core has aconstant thickness which is consisted of a number of teeth core.
 7. Themotor as claimed in claim 5, wherein said induction motor consisted of alaminated rotor core, a teeth core which is assembled on top of rotorcore and a short circuit ring that insulates between the teeth cores andexposes some part of the teeth core, and said rotor core has a structureconfiguration which is made of the multi slots with a constant distanceon the inner or outer circumference of a stator core circle in order tobe installed and said teeth core has a constant thickness which isconsisted of a number of teeth core.
 8. The motor as as claimed in claim5, wherein said induction motor is installed along the axial directionof the rotor to increase the rotator frame and a plurality of statorsare installed in the housing in order to face against said magnets inorder to increase the torque of the motor.
 9. The motor as claimed inclaim 6, wherein said induction motor is installed along the axialdirection of the rotor to increase the rotator frame and a plurality ofstators are installed in the housing in order to face against saidmagnets in order to increase the torque of the motor.
 10. The motor asclaimed in claim 7, wherein said induction motor is installed along theaxial direction of the rotor to increase the rotator frame and aplurality of stators are installed in the housing in order to faceagainst said magnets in order to increase the torque of the motor.